Blow-out damage prevention

Originally Posted by PopBeavers

I see they have a 6 wheel monitor for 15 bucks less. Not much of s discount. Might as well get the 16 wheel version for the extra 15 bucks.

Since I have 2 trucks and 2 trailers can I use a single monitor and just measure the pressure of the other trailer assuming I am alongside?

Wayne, if you have the unit on top of your dash, and if the 2nd vehicle were ahead or beside of you, it just might work. My Doran system will pick up the trailer from the driveway while the truck is in the garage with the doors closed, or visa versa. Beware though, that the tire sensors only transmit every 5 minutes or so if the tire pressures are within range, so you might hafta stay close to the other vehicle for a while until you recieve a transmission. Also, if they would be out of range during a pressure lose, or if you don't have good communications with them, then that driver would not know something is going on.

The Doran system does transmit almost immediately if there is a excessive lose (or gain).

Chap

Jacob:
We have the exact model TM as you do and share your concern regarding tire blowouts. Before our next trip I am going to upgrade to 15" wheels, which I hope will minimize or eliminate the problem. Our dealer (Custom RV in Anaheim CA) is now doing the mod. They say the spare fits the holder just fine and there is adequate clearance in the wheel wells. Cost is a little high at $500-$600 or so (estimated, don't know for sure), but you can't really put a price on piece of mind!

[B_and_D]

Dave, both of your ideas look/sound good. I don't ever think I've seen an RV of any type with a cage around the plumbing. I've seen a few RV's with substantial damage from blowouts; it seems the bigger the RV (and the tire) the worse the damage can be.

Originally Posted by ShrimpBurrito

B_and_D - I also don't like the idea that dirt, rain, and drips from the waste tank would land on this cage. What do you mean, "it would have been better if I had folded the sheet metal over so that it was folded over facing the bottom instead of the top."

The edges of my cage are folded over around the wire on each side. I put the side with the fold facing the underneath of the trailer vs. facing down towards the street. It creates another area where moisture & dirt could build up and remain, which would tend to make the sheet metal rust out faster. Probably the same thing would happen if it was facing the pavement, but it may drain better if it was facing down. I guess I could caulk it up.

Wow, checking once every 5 minutes is not continuous.

I checked my tires at a rest stop. I put my hand on the tires and hubs to confirm that they did not feel too hot. I checked sidewalls inside and outside and all looked normal. I check as much of the tread as I could see and it looked normal. Tire pressure had been checked with a digital gauge an hour earlier when we started out and the tires were cold, so I just looked at the bulge of the tire and it looked normal. I did not check the pressure with a gauge.

One hour later it went pop. We could hear it in the truck with the windows up, a/c on, radio off.

If the pressure is only checked once every 5 minutes, then if the pressure drops at a random point in time, on the average, it will be two and a half minutes before it is reported. Worst case it will not be reported for 4 minutes and 59 seconds. Two and a half minutes can let a lot of air out of the tire.

From my experience, from the time an event occurs that gets your attention, and you comprehend what it is and you pull over to the side of the freeway in a safe manner, that will easily take 2 minutes.

So you start loosing air at a significant rate. You get an alarm 2.5 minutes after it drops below the minimum acceptable value. You are stopped 2 minutes after that. Is that soon enough to prevent a blow out?

Anything that samples less often than every 30 seconds is not a lot of warning, imo.

There is a little bit of strange information regarding TPMS response times in this post so here is what I found on the system I currently have.

At the risk of being branded a sales person for Doran...

Taken from the Doran Website . . .

A Doran 360™ series tire pressure monitoring system is a compact system that delivers powerful results and protection. The Sensors are continually reading pressure and sending signals to the monitor about the air pressure in each tire around the clock. Each tire pressure monitoring system from the Doran tire pressure monitor product line consists of two basic components. . .

Key word being continually . . .

I cannot speak to what others have posted but here is a link if anyone is interested. http://www.doranmfg.com/tirepressuremonitorproducts.htm I test the system by removing the sensors and the monitor alarms instantly.

and if someone can build me a cage to protect that plumbing I'll buy it too!

Happy Camping!

[rtcassel]

http://www.tirepressuremonitor.com/details.htm states the following: The Sensors assess/read the air pressure in each tire 12,343 times every day! No other system on the market has this kind of coverage – most others only react to low pressure. Sensors assess pressures anywhere from 10 psi to 199 psi.

That's once every 7 seconds.

[wbmiller3]

I don't have the manual handy but on my model for sure the transmission is not every 7 seconds when the pressure is nominal. I know this because I plug in the panel and then screw on the sensors. It takes quite a while (way more than 7 seconds) to get the first reading.

However, when the sensors detect a significant drop in pressure (note clever use of word significant instead of a number because I don't have the manual) the transmission rate increases dramatically. I know this because a) I read it in the manual and b) I unscrewed the sensors while the panel was still plugged in. It took no time at all to get the alarm.

[rtcassel]

It appears that the TPMS reads the pressure every 7 seconds and transmits the pressure to the monitor every 5 minutes, unless the pressure is too low or high, in which case it transmits the pressure and an alert immediately.

Originally Posted by rtcassel

It appears that the TPMS reads the pressure every 7 seconds and transmits the pressure to the monitor every 5 minutes, unless the pressure is too low or high, in which case it transmits the pressure and an alert immediately.

I didn't mean to mislead Wayne or anyone with my last post. I think this post by rtcassel sums up all of the other posts into a nice little statement.

Wayne, if you have a pressure drop, it will alert you immediately.

Chap

I feel better about the data flow rate. Now I just have to justify the cost. I only have the two tires on the TM to monitor, because the new truck, 2008 GMC 2500HD, has it built in.

The other truck, 2002 Chevy 1500HD, does not have a built in monitor and it tows the single axle ATV trailer. So it would need to monitor 6 tires.

So I would need to monitors, 6 station and 2 station, plus 8 sensors.

Having had one blowout since I started driving in 1969, that is a lot of money for a rare event.

The TM blowout this year was probably caused by a combination of things:

1) outside temperature 106 degrees
2) Marathons were nearly 4 nears old and had been in service for 3 years
3) tire hit a small (we thought) pothole.

In hindsight we perhaps should have stopped twice to check the tire after hitting the pothole. Once as soon as possible to check for bubbles etc. and again 30 minutes later to check it again.

I don't think the tire pressure was very low, because it was quite a loud bang that we heard. It is my belief that it was a sudden drop in pressure when the tire blew, it was not a slow leak that occurred first, but there is no way to tell.